What Would Cause my ECM to go Bad 3 Important Facts

Are you still wounding what would cause my ECM to go bad, well there are several things that can cause the engine control module to fail. The engine control module is an electronic component which monitors and collect data from the various sensors to keep track of different part if the vehicle.

After collecting the various data, the ECM sends it to the PCM which sends back a processed data in form of signal for activities the ECM to carry out. The engine control module does not act on its own, rather based on the signal sent by the powertrain control module.

Enough of much talking, forget about the technical aspect, PCM is responsible for controlling the TCM and the TCM. Continue reading this article understand reasons for a failing ECM and symptoms of a bad ECM.

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Common causes of ECM Failure

  • Corrosion.

Corrosion is a all round problem that can happen to any part of the vehicle. The ECM board, wires, connectors can get corroded over time as a result of moisture.

Overtime, moisture can find its way into the engine control module through the wires and cause it to get corroded. Moisture and corrosion can lead to short ECM circuits or even electrical surges and voltage problems.

  • Moisture.

Moisture is bad it can cause your ECM to go bad. Mostly, moisture finds its way into the engine control module through wires and wiring. Moisture can as well cause the wiring harness around the electronic fuel solenoid to corrode.

If this happens, the injector sensor wiring harness will also become corroded together with the fuel solenoid. If your car was running well and then later failed to star, the ignition might have shorted the ECM.

  • Physical knocks and impact.

A physically impacted or knocked ECM is close to been dead. ECMs are fragile computer device that needs very careful handling. The device is equipped with tiny ICs, diode and transistors that can get spoilt when hit by something.

If you have to remove the Engine control module for inspection, please handle with very much care. Other causes of a failing engine control module includes the following.

  1. Damaged solenoid.
  2. Starter problems.
  3. Dead or weak battery.
  4. Bad jump starting practice.
  5. Loose wires and short circuit.
  6. Welding damages.

The powertrain control module otherwise know as the PCM or PCU is the master it controls both the ECM and the TCM. This puts the PCM in a place of great importance to make sure both the engine and the transmission are working as expected.

Types of Engine Control Modules

An Engine Control Module is a control system that monitors the engine, controls the air/fuel mixture, and adjusts ignition timing.
There are three main types of Engine Control Modules:

  • Engine Management
  • Direct Ignition Systems
  • Indirect Ignition Systems.

The Engine Control Module (ECM) is the nerve center of the engine. The ECM controls all of the engine’s functions, including ignition timing, fuel delivery, and air intake.

The ECM is a small computer that monitors and regulates a car’s engine performance. It does this by receiving input from sensors throughout the car.

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Functions of Engine Control Module (ECM)

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ECM is essentially the computer of the motor-control vehicle. It gathers and monitors data from various sensors and the monitoring systems that are embedded with it around each of the parts of a vehicle.

A standard coding tool provides codes, protocols and diagnostics for engine performance and diagnostics functions. It may be faulty, partially damaged or totally damaged.

Mud can corrode ECM seals, as common in older cars (5 to 10 years old). When the check engine’s light comes on and your ECM is full functioning the engine light might be indicative of a myriad of potential problems.

Electronic Throttle Body Injection Function?

Electronic Throttle Body Injection Systems were introduced in the 1970s. It was a technological advancement in the internal combustion engine.

The purpose of this system is to control the air intake and fuel injection, and it has been used by many automakers for over forty years.
Some of these systems are able to provide power when you need it, while others can help save fuel.

If your engine is not working correctly or needs an upgrade, then you should contact an automotive technician to find out if this system is right for your vehicle. The Electronic Throttle Body Injection System is a vital component in any car because it provides power when you need it and helps save fuel when needed

How do I know if my ECM is bad?

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While Engine control module is only concerned about the engine performance and wellbeing it is also as important as the PCM. The ECM is said to house different codes, protocols and standards diagnoses for trouble shooting engine performance.

When an ECM becomes bad it fails to respond, control and coordinate the activities of other unites in the car. Basically the Engine and the transmission would be in great danger as there would be no control over there activities. Below are the most common signs of a bad ECM

  • Check engine light comes on
  • Engine misfires
  • Poor fuel efficiency
  • Bad oil millage
  • Difficulty in starting
  • Poor engine performance
  • Rough idles

All of the above mention items are all symptoms that tells when the ECM is bad and might need replacement. However, this signs can also be localized to other mechanical problems including failing spark plugs and a clogged fuel pump.

If you are not sure of what problem could be please visit an auto repair shop or and auto electrician for proper checks. Do not start touching what you are not sure about before you cause more damage and expensive repairs.

Can ECM be repaired?

Can ECM be repaired? The answer is yes an ECM can be repaired if the problem is little and it has to be done by a professional. Repairing a bad ECM is way out of the skill set of an average driver or car owner.

The first, and easiest, way to repair an ECM is if there’s a problem with the power supply. Oftentimes, these can be repaired by a skilled mechanic or electrician, by rectifying any shorts or bad connections.

However, most ECM problems are a result of a bug in the software itself. However, this case of bug software problems isn’t common.

In addition to monitoring and regulating the engine’s performance, some advanced ECMs will also be able to control areas such as turbochargers and climate control systems as well as provide driver-assist features like collision avoidance or adaptive cruise control.

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Can I drive my car with a bad ECM?

Can I drive my car with a bad ECM? Yes you can drive with a bad engine control module but bear in mind that your engine will be at great risk. The primary function of the ECM is to keep track of each activities of the various part of the engine.

The ECM monitors most of the sensors in the engine bay in order to manage your vehicle’s air-fuel mixture and regulate the emission control systems. The main purpose of ECM is to regulate emission controls to make sure that the engine does not emit pollutants beyond specified parameters.

Because of the immense importance and role the ECM plays in making sure the engine runs properly, if it bad your vehicle might not even start. However in some modern cars even with a bad ECM the engine will still but managed properly, then it is not going to operate properly and then your car won’t work properly.

Is ECM and PCM the same thing?

ECM and PCM are often misunderstood and interchangeably used to mean the something which is wrong. The two are both electrical components that ensure control and proper functions in the car but one depends on the other.


PCM been and abbreviation of powertrain control module other call it powertrain control unit too. Power-train control module, abbreviated PCM, is an automotive component, a control unit, used on motor vehicles.

It is generally a combined controller consisting of the engine control unit (ECU) and the transmission control unit (TCU). The PCM commonly controls more than 100 factors in a car or truck.

While engine control module (ECM) is an electrical components that is concerned with all the activities in the engine bay. ECM monitor all different activities through various sensors in the engine bay.

This article seeks to answer the question what would make cause my ECM to go bad. If you have any more questions please feel free to ask us any question using the comment section.

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